1. Field of the Invention
This invention relates a box cutting method and an apparatus for carrying out the method, and particularly to a box cutting method and an apparatus for carrying out the method which is suitably used for collectively cutting desired upper edge portions of a plurality of boxes and opening top surfaces of the boxes without damaging or injuring goods contained in the boxes and without generating cutting chips.
2. Description of the Prior Art
As a conventional box cutting method and an apparatus for carrying out the method, there are some as disclosed in Japanese Patent Early Laid-open Publication No. Sho 63-11297, Japanses Utility Model Publication No. Sho 52-27178, etc.
The prior art disclosed in the above-mentioned Publications will be described. Japanese Patent Early Laid-open Publication No. Sho 63-11297 discloses a box cutting apparatus including a conveyor for transferring a box, and a cutter disposed at an upper part of the conveyor and adapted to cut an upper edge or the vicinity of the upper edge of the box in accordance with the movement of the conveyor.
Similarly, Japanese Utility Model Publication No. Sho 52-27178 discloses a package unpacking device comprising a bottom cutter and an upper cutter for cutting both sides of a bottom portion of a package and an upper portion thereof.
However, the prior art has the following problems.
That is, the box cutting apparatus disclosed in Japanese Patent Early Laid-open Publication No. Sho 63-11297 and the package unpacking device disclosed in Japanese Utility Model Publication No. Sho 52-27178 are designed such that an upper edge portion or an upper portion of a transferring box is cut by moving the box with respect to a cutter body which is held in a predetermined position. Accordingly, the box is swayed while it is transferred and the box is deformed by resistance when it is cut, which makes it impossible to cut the box at a desired place correctly. The result is that goods contained in the box are damaged and the box is cut in a wrong manner.
Also, the above-mentioned box cutting apparatus or the above-mentioned package unpacking device is designed such that the boxes are individually cut. Accordingly, cutting efficiency is low. In addition, the Publications do not disclose nor even suggest that a plurality of boxes are collectively cut.
Further, the above-mentioned box cutting apparatus or the above-mentioned package unpacking device does not disclose nor even suggest that boxes, which are being transferred, are cut or not cut according to necessity. In other words, the Publications do not disclose nor even suggest that only an upper edge portion of a desired box is cut.
Furthermore, the above-mentioned box cutting apparatus or the above-mentioned package unpacking device is designed such that an upper edge portion or an upper portion of a box is cut without putting aside goods contained in the box inwardly. Accordingly, goods contained in the box are sometimes damaged.
Still further, the above-mentioned box cutting apparatus is designed such that a pair of opposite cutting knives are inserted with respect to a top surface and a side surface of a box to cut down an upper edge portion of the box at angles. Accordingly, the cutting pieces or cutting chips must be removed.
Still further, the above-mentioned box cutting apparatus or the above-mentioned package unpacking device is designed such that all boxes are cut at an equal cutting depth. Accordingly, the box cannot be correctly cut at a desired deep position. The result is that goods contained in the box are sometimes damaged and the box is sometimes cut in a wrong manner.
Moreover, the above-mentioned box cutting apparatus or the above-mentioned package unpacking device does not disclose nor even suggest that a cutting knife position of a box is determined with reference to a position where a clamping plate pressing the side surface of the box clamps the box.